I/O UDP

Analog Section

The Analog Section of the UDP packet is comprised of I/O data for each enabled Analog channel.

Note: If the IOLAN I/O model does not support Analog channels, the Analog Channel Data subsection of the Analog Section will NOT be present in the UDP packet.

Section

Channel

 

Analog Channel Data (for each enabled channel)

 

Length

Enabled

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2 Bytes

1 Byte

curRawValue

minRawValue

maxRawValue

curEngValue

minEngValue

maxEngValue

 

 

2 Bytes

2 Bytes

2 Bytes

4 Bytes

4 Bytes

4 Bytes

 

 

 

 

 

 

 

 

zSection Length—The total length of the Analog section (this value will vary, the field length is 2 Bytes). This value will vary because it will contain one Analog Channel Data subsection (18 bytes) for each Analog channel that is enabled.

zChannel Enabled—The Channel Enabled field is 1 byte in least significant bit order, for each channel. If the channel is enabled, the bit is set to 1. If the channel is disabled, the bit is set to 0 (zero).

Channel Enabled (1 Byte, one bit for each channel)

Channel 4 Channel 3 Channel 2 Channel 1

zAnalog Channel Data—Consists of Analog Channel Data for each enabled Analog channel on the IOLAN. If an Analog channel is disabled, there is no data for that channel. Therefore, the Analog Section will contain the Section Length value, the Channel Enabled value, and 18 bytes of I/O data for each enabled Analog channel. For example, an IOLAN I/O model with four Analog channels that has only three of those Analog channels enabled will contain 54 bytes of Analog Channel Data (18 bytes * 3 Analog channels).

The following values make up the Analog Channel Data for each enabled Analog channel: z curRawValue—The current raw value received by the channel.

z minRawValue—The minimum raw value received by the channel until it is cleared.

z maxRawValue—The maximum raw value received from the channel until it is cleared.

z curEngValue—The current raw value that has been converted to voltage/current for Analog or Celsius/Fahrenheit for Temperature.

z minEngValue—The minimum raw value that has been converted to voltage/current for Analog or Celsius/Fahrenheit for Temperature until it is cleared.

z maxEngValue—The maximum raw value that has been converted to voltage/current for Analog or Celsius/Fahrenheit for Temperature until it is cleared.

265

Page 265
Image 265
Perle Systems SCS, STS manual Analog Section, Section Channel, Length Enabled